A known radio communication system comprises a first radio access network, based on a first radio access technology (RAT) (or a first radio access network (RAN) layer), wherein the first radio access network provides limited coverage. Furthermore, the radio communication system comprises a second radio access network, based on a second radio access technology (or a second RAN layer). The second radio access network provides a more general coverage than the first radio access network. In such a radio communication system signalling and processing due to mobility events, such as active mode handover (HO) and idle mode movements of a user equipment, may cause the radio communication system to be overloaded or at least loaded to an unnecessarily high extent.
Depending on deployment scenarios, initial LTE (Long Term Evolution) rollouts may be one such case.
Another case may be when only a first radio access network is comprised in the radio communication system. Then, indoor verses outdoor coverage may differ from each other, because different carriers (or frequency bands) may be used for indoor versus outdoor coverage.
In another scenario, a WLAN (Wireless Local Area Network) network may be used to provide access to mobile network services in a mobile communication system, comprising a mobile radio access network and a mobile core network. Each time a user equipment moves between WLAN coverage and mobile network coverage, the mobile core network needs to be informed. Hence, signalling and processing due to mobility events, which occurs for example when the user equipment moves between WLAN and mobile network coverage, needs to be handled by the mobile core network.
In a further scenario, employing femto base station, similar load issues are likely to occur.
A problem in the above mentioned scenarios is, hence, that the signalling and processing due to mobility events puts an unnecessarily large load on the radio communication system.